Various types of digital projectors are known in the art. One common type uses a combination of dichroic optics, three light modulator chips, and combining optics. The dichroic optics separate the light into primary color beams so that each beam may be modulated by one of the three light modulator chips. After modulation, the light beams are recombined before being displayed on a display surface. Providing three light modulator chips increases the size and cost of this type of projector.
As an alternative, the use of LCD chips or panels can be somewhat cost effective. However, LCD panels require polarizing the light. Polarizing the light reduces output intensity while adding the cost of polarizing.
Another type of projector utilizes a combination of sequential color generation, such as a white light source passing through a rotating color filter wheel, and a micro-mirror array. A significant portion of the potential color saturation is lost and visual artifacts such as color separation result from using sequential color. Designs such as scrolling color wheels can partially mitigate these issues but add complexity and difficult timing and assembly issues to the system.